Student copy of notes - User Web Areas at the University of York
... / low energy) to blue hot (shorter wavelength / higher energy). But this shift in mean photon energy is not restricted only to the visible part of the electromagnetic spectrum. Very low temperature objects emit principally in the infrared or microwave regions. At the other end of the spectrum very h ...
... / low energy) to blue hot (shorter wavelength / higher energy). But this shift in mean photon energy is not restricted only to the visible part of the electromagnetic spectrum. Very low temperature objects emit principally in the infrared or microwave regions. At the other end of the spectrum very h ...
The Circumstellar Environments of Young Stars at AU Scales
... measured NIR sizes are tightly contained within the sublimation radii of directly heated grey dust with sublimation temperatures of 1000 K−1500 K under the assumption that dust grains radiate over the full solid angle (e.g., no backwarming, solid lines in Fig. 2). If instead we assume that the dust ...
... measured NIR sizes are tightly contained within the sublimation radii of directly heated grey dust with sublimation temperatures of 1000 K−1500 K under the assumption that dust grains radiate over the full solid angle (e.g., no backwarming, solid lines in Fig. 2). If instead we assume that the dust ...
tr-2004-81
... systems (DBMS) have been introduced as useful tools to manage metadata, data, resources, workflows, etc [24] [25][26], the presence of databases is minimal in science applications running on the Grid. Today the typical dataintensive science Grid application still uses flat files to process and store ...
... systems (DBMS) have been introduced as useful tools to manage metadata, data, resources, workflows, etc [24] [25][26], the presence of databases is minimal in science applications running on the Grid. Today the typical dataintensive science Grid application still uses flat files to process and store ...
Galactic spiral structure - Proceedings of the Royal Society A
... We describe the structure and composition of six major stellar streams in a population of 20 574 local stars in the New Hipparcos Reduction with known radial velocities. We find that, once fast moving stars are excluded, almost all stars belong to one of these streams. The results of our investigatio ...
... We describe the structure and composition of six major stellar streams in a population of 20 574 local stars in the New Hipparcos Reduction with known radial velocities. We find that, once fast moving stars are excluded, almost all stars belong to one of these streams. The results of our investigatio ...
TMT Science Overview - GSMT Program Office
... TMT MCAO. The red, blue and green lines represent three input stellar populations. (K. Olsen, NOAO) ...
... TMT MCAO. The red, blue and green lines represent three input stellar populations. (K. Olsen, NOAO) ...
Shape effects in optical properties of composite dust particles
... grains) to exemplify which information are obtained from comparison to the coated sphere of same composition. Other models depending on a few number of parameters could be used as well. A more sophisticated example is given in Kimura et al (2003), with aggregates of 1compound monodispersed grains. I ...
... grains) to exemplify which information are obtained from comparison to the coated sphere of same composition. Other models depending on a few number of parameters could be used as well. A more sophisticated example is given in Kimura et al (2003), with aggregates of 1compound monodispersed grains. I ...
The incidence of stellar mergers and mass gainers among massive
... We assume that contact binaries merge. During the coalescence we assume in our standard simulations that a fraction µloss = 0.1 of the system mass is lost during the merger taking away the excess angular momentum. When investigating the uncertainties we consider the case that mass loss can be neglec ...
... We assume that contact binaries merge. During the coalescence we assume in our standard simulations that a fraction µloss = 0.1 of the system mass is lost during the merger taking away the excess angular momentum. When investigating the uncertainties we consider the case that mass loss can be neglec ...
The white dwarf cooling sequence of 47 Tucanae
... errors in the simulated population explains why our model is superior, we found that the observed break cannot be explained by the sudden increase in photometric errors for stars with magnitudes larger than 25 mag. Thus, the reason for the observed break in the empirical curve must be related to eit ...
... errors in the simulated population explains why our model is superior, we found that the observed break cannot be explained by the sudden increase in photometric errors for stars with magnitudes larger than 25 mag. Thus, the reason for the observed break in the empirical curve must be related to eit ...
Multiple Linear Regression
... ? give the relative velocity and the distance of 24 galaxies, according to measurements made using the Hubble Space Telescope – the data are contained in the gamair package accompanying ?, see Table 6.1. Velocities are assessed by measuring the Doppler red shift in the spectrum of light observed fro ...
... ? give the relative velocity and the distance of 24 galaxies, according to measurements made using the Hubble Space Telescope – the data are contained in the gamair package accompanying ?, see Table 6.1. Velocities are assessed by measuring the Doppler red shift in the spectrum of light observed fro ...
A self-consistent model of isolated neutron stars: the case of the X
... Context. We present a unified explanation for the observed properties of the isolated neutron star RX J0720.4-3125 by obtaining a self-consistent model that accounts simultaneously for the observed X-ray spectrum and optical excess, the pulsed fraction, the observed spectral feature around 0.3 keV, ...
... Context. We present a unified explanation for the observed properties of the isolated neutron star RX J0720.4-3125 by obtaining a self-consistent model that accounts simultaneously for the observed X-ray spectrum and optical excess, the pulsed fraction, the observed spectral feature around 0.3 keV, ...
A novel L-band imaging search for giant planets in the Tucana and β
... of typically 5 astronomical units. A planet with a mass ≥1 MJup at distances ≥5 AU around AU Mic can be excluded at the time of our observations. The absence of detected planets sets constraints on the frequency distribution and maximum orbital distance of giant exoplanets. For example, a radial dis ...
... of typically 5 astronomical units. A planet with a mass ≥1 MJup at distances ≥5 AU around AU Mic can be excluded at the time of our observations. The absence of detected planets sets constraints on the frequency distribution and maximum orbital distance of giant exoplanets. For example, a radial dis ...
Influence of extreme ultraviolet radiation on the Pv ionization fraction
... on the square of the density. Moreover, the ultraviolet P V resonance lines indicate a possible need for an even stronger reduction of hot star mass-loss rates, provided that P V is a dominant ionization stage of phosphorus, at least in some hot stars. The latter assumption is challenged by the poss ...
... on the square of the density. Moreover, the ultraviolet P V resonance lines indicate a possible need for an even stronger reduction of hot star mass-loss rates, provided that P V is a dominant ionization stage of phosphorus, at least in some hot stars. The latter assumption is challenged by the poss ...
Cosmological Implications of Trace
... within cold diffuse clouds of H2 , residual 3 or H repulsive Coulomb forces between these few unbalanced charges are comparable to the gravitational attractions between the many nucleons. Thus, trace-charged dark matter is inert with respect to static electrogravitional self-attractions, but respond ...
... within cold diffuse clouds of H2 , residual 3 or H repulsive Coulomb forces between these few unbalanced charges are comparable to the gravitational attractions between the many nucleons. Thus, trace-charged dark matter is inert with respect to static electrogravitional self-attractions, but respond ...
Wroclaw_VanGrootel
... convective He-burning core (I), radiative He mantle (II) and very thin H-rich envelope (III) lifetime of ~ 108 yr (100 Myr) on EHB, then evolve as low-mass white dwarfs At least 50% of sdB stars reside in binary systems, generally in close orbit (Porb 10 days) ...
... convective He-burning core (I), radiative He mantle (II) and very thin H-rich envelope (III) lifetime of ~ 108 yr (100 Myr) on EHB, then evolve as low-mass white dwarfs At least 50% of sdB stars reside in binary systems, generally in close orbit (Porb 10 days) ...
Diapositiva 1
... The error depend on the Γ angle (0.5 μas accuracy) Parallactic displacement along the great cicle Sun-Star Sensitivity AL is proportional to sin ξ sin Γ ξ = Sun-spin axis angle = 45º for Gaia Γ = basic angle = 106.5º for Gaia Optimal values between astrometry requirements - that call for a large ang ...
... The error depend on the Γ angle (0.5 μas accuracy) Parallactic displacement along the great cicle Sun-Star Sensitivity AL is proportional to sin ξ sin Γ ξ = Sun-spin axis angle = 45º for Gaia Γ = basic angle = 106.5º for Gaia Optimal values between astrometry requirements - that call for a large ang ...
Cataclysmic Cosmic Events and How to Observe Them www.springer.com/series/5338
... watts in the cases of the most extreme quasars/quasi-stellar objects (QSOs), or tens of trillions the power output of our own Sun. Active galaxies and supernovae are, arguably, only challenged in violence by one category of object, gamma-ray bursts, or ‘GRBs.’ Once again, black holes are thought to ...
... watts in the cases of the most extreme quasars/quasi-stellar objects (QSOs), or tens of trillions the power output of our own Sun. Active galaxies and supernovae are, arguably, only challenged in violence by one category of object, gamma-ray bursts, or ‘GRBs.’ Once again, black holes are thought to ...
Astronomical spectroscopy
Astronomical spectroscopy is the study of astronomy using the techniques of spectroscopy to measure the spectrum of electromagnetic radiation, including visible light, which radiates from stars and other hot celestial objects. Spectroscopy can be used to derive many properties of distant stars and galaxies, such as their chemical composition, temperature, density, mass, distance, luminosity, and relative motion using Doppler shift measurements.